Process for producing polychromatic screens, plates, films, and paper for color photography.



UNITED STATES PATENT OFFICE.

JAN SZCZEPANIK, OF LUISENHOF, NEAR DRESIDEN, GERMANY.

PROCESS FOR PRODUCING POLYCHROMATIC SCREENS, PLATES, FILMS, AND PAPER FOR COLOR PHOTOGRAPHY.

1,089,602. npniawin To all whom it may concern Be it known that I, JAN SZGZEPANIK, en-

gineer, subject of the Austro-Hungarian Emperor, residing at Weisser Hirsch, Luisenhof, near Dresden, in Germany, have invented new and useful Improvements in Processes for Producing Polychromatic Screens, Plates, Films, and Paper for Color "Photography, of ,which the following is a specification.

; The resent invention relates to a method ofpr ucing polychromatic screens, and especially three-color screens, for the production of photographs in natural colors.

, This invention further relates to the making of photographic plates, films, and paper for color photography.

The said method is based on the known property possessed by various dyestuflts, of behaving differentially or'selectively toward Other substances to be stained therewith. Thus, for instance, a dry collodion film is at once stained blue on being dipped in an aqueous solution of basic methylene blue containing a little alcohol, whereas it stains with.,.difiiculty on being dipped in an even purely alcoholic solution of acid erythrosin. On the other hand a dry gelatin film which is .d-iflicult to stain by immersion in even a 90 purely aqueous solution of methylene blue,

acquires a stain at once when dipped in an holic solution of erythrosin containin only a little water. If the two dyestu solutions be mixed, and a film of gelatin and.

one of collodion be dipped simultaneously in solutionstainedt erewith into 'a gelatin.

' the production of three eolor or polychrome the mixture, the dyestuffs separate, the collodiontaking a pure blue stain while the gelatin is stained pure red. If a solution of gelatin that has-been stained with methylene blue, and treated with a little alcohol for v the purpflse .ofsoftening the collodion, be

applied to .dry collodion film, the' 1nethylenebluemig'rates from the gelatin into the collodion. -O0nversely,erythrosin will migrate almost com letely" from a collodion support. This differential behavior of the a id-mid basic dyest-ufi's toward certain substances, =such asgelatin, collodion, lacs, gums, resins, caoutchouc and many others, is, according to. the present method, utilizedfor scree in i the .follow' Im elxf n me y th tytheszsuppont int n d to receive e sem and consisting,- as already known; of

Specification of Letters Patent.

Application filed August 6, 1908. Serial No. 447,336.

Patented Mar. 10, 1914.

a film of gelatin, collodion or the like, or carrying such a film, is brought into contact with the desired dyestufi's, which are mixed with substances for which these dyestufis have a less powerful afiinity than they have for the said film of collodion or gelatin. The dyestulfs then migrate from their carriers into the gelatin or collodion film, and after the said dyestufi' carriers have been removed, as for instance by washing, the polychromatic, e. g. three-color, screen is left in a finished state. y

The practical manufacture of the screens is carried out in the following manner: Three solutions of gelatin are prepared, and each of them is stained with a dyestufi possessing a stronger atfinity for collodion than it has for the vehicle, e. g. gelatin. The stained solutions are then evaporated to dryness and ground to fine powder. The three powders are mixed and applied to afreshly prepared and therefore still rather sticky collodionized support, either by sifting them through sieves on to the support traveling underneath, or else by means of a dusting-on device. -The dyestuffs migrate from the powder int-o the collodionized surface and then the powder, now colorless, is removed by washing. .Although in this method, the colored powders overlie each other to a lar e extent, no interchange of their dyestu 's occurs but on the other hand uncolorecl patchesmay remain in many parts of the support, owing to no color having been absorbed through defective contact between the powder and the substratum. This defect, however, may be remedied, as for example by dusting-on only two differently colored powders, and producing the thrid color by treatingthe-support in a bath containing the third dyestufi' dissolved in a substance of such kind (6. g. gelatin) that the dyestufi will migrate'from it into the collodion, the gelatin being then removed by washing. Or, again, three differently colored powders may be dusted on, a smaller quantity being taken of one than of the others, and the treatment then completed. as above.

Instead of. gelatin, a solution of gum arabic, for-exaniiiple, may be used-for aibsorbgelatininsteadof being collodionized, the

reverse method is adopted, that is to say the dyestufis are dissolved in collodion, dried and dusted on the support. In this case of course, the dyestuffs dissolved in the collodion must be suchas exhibit a greater aflinity for gelatin and will therefore migrate from the colored collodion powder into the gelatin film. V 1

- Instead of dusting the support over with colored powders, it may be sprayed directly .with the colored liquids, for instance with the above-named three colored gelatin solutions or the like, simultaneously or in succession. In this case the following procedure may be adopted as an example: A collodionized support issprayed first with, for instance, a red colored solution of caoutchouc (in chloroform), then with a bluecolored solution of gelatin, and the plate finally bathed in a solution of the third dyestufi' (yellow-green). The dyestufi' migrates from the solutions of caoutchouc and gelatin into the collodion, and the caoutchouc and gelatin are removed by washing,

whereupon the support appears stained with the three colors. The third color is not necessarily applied by bathing in a solution of thedyestufi', but may also be applied by spraying. By using dyestufi solutions that will not mix together, they..may all be applied at the same time by means of two or three spraying devices as the case may be. Another typical method consists in first covering a collodionized support, such for regular figures (dots again for example) are applied crosswise, so as to cover only one- 1 third of the surface of the screen, by means,

for example, of a yellow-green varnish color. been distributed with geometric uniformity, the two groups of figures or dots will overlap each other to an extent equal to one-sixth of the area of the screen. A collodion film prepared in this way, is, for instance, bathed for a short time in the above cited mixture consistin of a. solution of methylene blue and eryt rosin. Since the fatty yellowishgreen color will not absorb any of the dyestufl solutions, only the parts left uncovered by the fatty color, and consisting, one half of collodion and the other half of gelatin, will be stained. Since the gelatin is stained red and the collodion blue in such a mixture of dyestufis, it is clear that a three-color screen, free from imperfections of covering canbe obtained by this means. Of course, separate baths of erythrosin and methylene blue, or similar dyestufis, may be used in- Provided the figures or dots have' not absorbed either by the fatty color (which will not take up any dyestufi' at all) methylene blue or similar dyestufi, which is or by the gelatin. Both the stained gelatin over the parts in contactwith the fattycolor andthe gelatin from which the rhodamin has been, absorbed by the-underlying collodion, are then removed by a short bathing in lukewarm water, leaving a completed three-color mosaic free from any imperfections of covering.

Another method of carrying out this process consists in the following:Three. filaments stained with difierent primary colors are prepared from stained solutions of latin or the like, and are made into a tissue of fabric; or three powders made from differently colored gelatin are mixed together and pressed to form a block; or thin Y leaves of gelatin stained with diiferent colors are laid alternately one upon another until a block ofa certain thickness is obtained, this being then divided into two. parts by a vertical cut. The fabric, or comwhereupon the adjacent and uniformly d1s-" tributed dyestuffs in these blocks migrate into the collodion. These printing blocks may be used for the same purpose more than removed b washing. If the support begelatinized, en the printing must be made of stainedcollodion, the dyestuffs used in this event being such as will migrate into gelatin.

In order, for optical reasons, to dispense with an insulating layer between the threecolor screen and the panchromatic emulsion, the screen stratum, on the surface. of which the patches of color are carried, must consist of some material other than'that of the panchromatic stratum. If the panchromatic stratum be a gelatin-silver-bromid emulsion, the screen support must be made of collodion or caoutchouc for instance; but if the panchromatic stratum consist of collodion 0r similar-substances, then the support carrying the screen must no longer be of collodion but of some material such as gelatin.

For the production of photographic pictures in colors, with the aid of the threecolor screen, on opaque supports, such as paper for instance, the support is first of all rendered transparentby means of oils, fats,

.or the like, and is 'then provided with a stead of the mixed bath. again, the fatty,

transparent layer of collodion, gelatin,

once, while any traces of gelatin adhering to the support after the impression may be caoutchouc or the like, suitable for carrying the three-color screen, on which layer a threecolor mosaic is produced by the means already described, and towhich layer a panchromatic stratum is applied. After exposure through the transparent support, and after the negative or positive silver image is finished, the substances (oils, fats or the like) used for rendering the support transparent are removed by a bath of suitable material such as ether, benzin, chloroform, alcohol, etc., whereby the original opaque appearance of the support, 6. 9., paper, is restored. The substances used for making the paper transparent may be suitably colored, for instance orange or yellow, in order I (since the exposure must be made through the support) to replace the usual yellow filter necessary for the correction of the still imperfectly panchromatic strata used, the said color being removed after the paper has been washed free from the oil, or like matter.

Instead of providing the three-color screen with a panchromatic silver-bromid emulsion, which hasto be developed after exposure, it is advisable for copying purposes, to provide it with a printing-out emulsion, as for example a silver-chlorid emulsion, that has been rendered panchromatic by suitable sen-- sitizers, thus afi'ording the operator an opportunity of watching the progress of the copying, in a weak light.

I claim:

1. The method of producing polychromatic screens for color photography, comprising simultaneously applying to a support a number of dyes contained in vehicles comprising material for which said dyes have a lower affinity than for the. support so that said dyes will migrate into the sup-- port from the vehicles, and then removing the vehicles from the support .by washing.

2. The method of producing polychromatic screens for color photography, comprising applying to a support discrete dyecontalning vehicles comprising material for which said dyes have a lower aifinity-than for the support so that said dyes will mi-' grate into said support from the vehicles,

and then removing the vehicles from the support by washing.

3. The method of producing polychromatic screens for color photography, comprising projecting upon a support discrete dye-containing vehicles compr1sing material port so that said dyes wi I migrate into said support from the vehicles, and then removing the vehicles from the support by washing.

5. The process of manufacturing polychromatic screens for color photography 1n natural colors, which comprises bringing into close contact with a suitable support, a suflicient number of provisional dye-stuff carriers, such carriers being provided with dyes having a lower aflinity for the carriers than for the support so that said dyes Wlll migrate into the support from the provisional carriers, and then removing the provisional carriers.

6. The process of making polychromatic media, such as plates, films, and paper, for

color photo raphy in natural colors, com,

prising app ying to a base a support having an aflinity for coloring matter, applying coloring matter to sa1d support by m1- gration, and then coyermg said colored support by a light-sens1t1ve agent earr1ed 1n a vehicle having a different ailinity for said coloring" matter than said support.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

a JAN SZCZEPANIK.

Witnesses;

ULYSSES J. BYWATER, PAUL ARRAS. 

